The equivalent expression at the point where it is undefined is ∞
Undefined expression
Given the trigonometry expression
tanαcos(2α)
From trigonometry identity;
tanα = sinα/cosα
The expression above will become:
tanαcos(2α) = sinαcos(2α)/cosα
The function is undefined at the point where cosα = 0
cosα = 0
α = arccos(0)
α = 90degrees
Substitute α = 90degrees into the expression;
tanαcos(2α) = tan 90 cos(180)
tanαcos(2α) = ∞
Hence the equivalent expression at the point where it is undefined is ∞
Learn more on trigonometry identity here: https://brainly.com/question/24496175
